title: [Influence of the season and of gestation on the plasma concentration of thyroid hormones: triiodothyronine (T3) and thyroxine (T4) in Sahel Peulh ewes].
abstract: Seasonal and gestational variations of triiodothyronine (T3) and thyroxine (T4) plasma concentrations were evaluated in 12 pregnant and 6 non pregnant adult Sahel Peulh ewes. Blood samples were drawn from all animals at different dates for radio-immunoassay. In this particular breed of sheep, plasma triiodothyronine and thyroxine levels did not present significant variations from the beginning of the cool season (December) until the end of the dry warm season (May). On the contrary, a highly significant rise of hormones (P less than 0.01) was observed at the onset of the humid warm season (June). Moreover, a significant decrease of thyroid hormone plasma levels (P less than or equal to 0.05) greater for thyroxine than triiodothyronine was observed at the end of gestation, particularly in twin pregnancies. At birth, the thyroxine plasma level was higher in single than in twin lambs (139.6 +/- 66.5 vs 110.5 +/- 43.8 ng/ml).
authors.affiliation: Ecole inter-Etats des sciences et médecine vétérinaires, Département de physiologie, pharmacodynamie, thérapeutique, Dakar, Sénégal.
authors.forename: M
authors.initials: M
authors.lastname: Assane
authors.forename: A
authors.initials: A
authors.lastname: Sere
mesh_terms: D000818:Animals; D000831:Animals, Newborn / Q000097:blood*; D005260:Female; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000097:blood*; D011863:Radioimmunoassay; D012016:Reference Values; D012621:Seasons; D012675:Senegal; D012756:Sheep / Q000097:blood*; D013974:Thyroxine / Q000097:blood*; D014284:Triiodothyronine / Q000097:blood*
chemical_list: D014284:Triiodothyronine; D013974:Thyroxine
vernacular_title: Influence de la saison et de la gestation sur la concentration plasmatique des hormones thyroïdiennes: triiodothyronine (T3) et thyroxine (T4), chez la brebis peulh du Sahel.